1 /*
2  * PCI Dynamic LPAR, PCI Hot Plug and PCI EEH recovery code
3  * for RPA-compliant PPC64 platform.
4  * Copyright (C) 2003 Linda Xie <lxie@us.ibm.com>
5  * Copyright (C) 2005 International Business Machines
6  *
7  * Updates, 2005, John Rose <johnrose@austin.ibm.com>
8  * Updates, 2005, Linas Vepstas <linas@austin.ibm.com>
9  *
10  * All rights reserved.
11  *
12  * This program is free software; you can redistribute it and/or modify
13  * it under the terms of the GNU General Public License as published by
14  * the Free Software Foundation; either version 2 of the License, or (at
15  * your option) any later version.
16  *
17  * This program is distributed in the hope that it will be useful, but
18  * WITHOUT ANY WARRANTY; without even the implied warranty of
19  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
20  * NON INFRINGEMENT.  See the GNU General Public License for more
21  * details.
22  *
23  * You should have received a copy of the GNU General Public License
24  * along with this program; if not, write to the Free Software
25  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
26  */
27 
28 #include <linux/pci.h>
29 #include <asm/pci-bridge.h>
30 #include <asm/ppc-pci.h>
31 #include <asm/firmware.h>
32 #include <asm/eeh.h>
33 
34 static struct pci_bus *
35 find_bus_among_children(struct pci_bus *bus,
36                         struct device_node *dn)
37 {
38 	struct pci_bus *child = NULL;
39 	struct list_head *tmp;
40 	struct device_node *busdn;
41 
42 	busdn = pci_bus_to_OF_node(bus);
43 	if (busdn == dn)
44 		return bus;
45 
46 	list_for_each(tmp, &bus->children) {
47 		child = find_bus_among_children(pci_bus_b(tmp), dn);
48 		if (child)
49 			break;
50 	};
51 	return child;
52 }
53 
54 struct pci_bus *
55 pcibios_find_pci_bus(struct device_node *dn)
56 {
57 	struct pci_dn *pdn = dn->data;
58 
59 	if (!pdn  || !pdn->phb || !pdn->phb->bus)
60 		return NULL;
61 
62 	return find_bus_among_children(pdn->phb->bus, dn);
63 }
64 EXPORT_SYMBOL_GPL(pcibios_find_pci_bus);
65 
66 /**
67  * pcibios_remove_pci_devices - remove all devices under this bus
68  *
69  * Remove all of the PCI devices under this bus both from the
70  * linux pci device tree, and from the powerpc EEH address cache.
71  */
72 void
73 pcibios_remove_pci_devices(struct pci_bus *bus)
74 {
75 	struct pci_dev *dev, *tmp;
76 
77 	list_for_each_entry_safe(dev, tmp, &bus->devices, bus_list) {
78 		eeh_remove_bus_device(dev);
79 		pci_remove_bus_device(dev);
80 	}
81 }
82 EXPORT_SYMBOL_GPL(pcibios_remove_pci_devices);
83 
84 /* Must be called before pci_bus_add_devices */
85 void
86 pcibios_fixup_new_pci_devices(struct pci_bus *bus)
87 {
88 	struct pci_dev *dev;
89 
90 	list_for_each_entry(dev, &bus->devices, bus_list) {
91 		/*
92 		 * Skip already-present devices (which are on the
93 		 * global device list.)
94 		 */
95 		if (list_empty(&dev->global_list)) {
96 			int i;
97 
98 			/* Fill device archdata and setup iommu table */
99 			pcibios_setup_new_device(dev);
100 
101 			pci_read_irq_line(dev);
102 			for (i = 0; i < PCI_NUM_RESOURCES; i++) {
103 				struct resource *r = &dev->resource[i];
104 
105 				if (r->parent || !r->start || !r->flags)
106 					continue;
107 				pci_claim_resource(dev, i);
108 			}
109 		}
110 	}
111 }
112 EXPORT_SYMBOL_GPL(pcibios_fixup_new_pci_devices);
113 
114 static int
115 pcibios_pci_config_bridge(struct pci_dev *dev)
116 {
117 	u8 sec_busno;
118 	struct pci_bus *child_bus;
119 
120 	/* Get busno of downstream bus */
121 	pci_read_config_byte(dev, PCI_SECONDARY_BUS, &sec_busno);
122 
123 	/* Add to children of PCI bridge dev->bus */
124 	child_bus = pci_add_new_bus(dev->bus, dev, sec_busno);
125 	if (!child_bus) {
126 		printk (KERN_ERR "%s: could not add second bus\n", __FUNCTION__);
127 		return -EIO;
128 	}
129 	sprintf(child_bus->name, "PCI Bus #%02x", child_bus->number);
130 
131 	pci_scan_child_bus(child_bus);
132 
133 	/* Fixup new pci devices */
134 	pcibios_fixup_new_pci_devices(child_bus);
135 
136 	/* Make the discovered devices available */
137 	pci_bus_add_devices(child_bus);
138 
139 	eeh_add_device_tree_late(child_bus);
140 	return 0;
141 }
142 
143 /**
144  * pcibios_add_pci_devices - adds new pci devices to bus
145  *
146  * This routine will find and fixup new pci devices under
147  * the indicated bus. This routine presumes that there
148  * might already be some devices under this bridge, so
149  * it carefully tries to add only new devices.  (And that
150  * is how this routine differs from other, similar pcibios
151  * routines.)
152  */
153 void
154 pcibios_add_pci_devices(struct pci_bus * bus)
155 {
156 	int slotno, num, mode;
157 	struct pci_dev *dev;
158 	struct device_node *dn = pci_bus_to_OF_node(bus);
159 
160 	eeh_add_device_tree_early(dn);
161 
162 	mode = PCI_PROBE_NORMAL;
163 	if (ppc_md.pci_probe_mode)
164 		mode = ppc_md.pci_probe_mode(bus);
165 
166 	if (mode == PCI_PROBE_DEVTREE) {
167 		/* use ofdt-based probe */
168 		of_scan_bus(dn, bus);
169 		if (!list_empty(&bus->devices)) {
170 			pcibios_fixup_new_pci_devices(bus);
171 			pci_bus_add_devices(bus);
172 			eeh_add_device_tree_late(bus);
173 		}
174 	} else if (mode == PCI_PROBE_NORMAL) {
175 		/* use legacy probe */
176 		slotno = PCI_SLOT(PCI_DN(dn->child)->devfn);
177 		num = pci_scan_slot(bus, PCI_DEVFN(slotno, 0));
178 		if (num) {
179 			pcibios_fixup_new_pci_devices(bus);
180 			pci_bus_add_devices(bus);
181 			eeh_add_device_tree_late(bus);
182 		}
183 
184 		list_for_each_entry(dev, &bus->devices, bus_list)
185 			if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE)
186 				pcibios_pci_config_bridge(dev);
187 	}
188 }
189 EXPORT_SYMBOL_GPL(pcibios_add_pci_devices);
190 
191 struct pci_controller * __devinit init_phb_dynamic(struct device_node *dn)
192 {
193 	struct pci_controller *phb;
194 	int primary;
195 
196 	primary = list_empty(&hose_list);
197 	phb = pcibios_alloc_controller(dn);
198 	if (!phb)
199 		return NULL;
200 	rtas_setup_phb(phb);
201 	pci_process_bridge_OF_ranges(phb, dn, 0);
202 
203 	pci_devs_phb_init_dynamic(phb);
204 
205 	if (dn->child)
206 		eeh_add_device_tree_early(dn);
207 
208 	scan_phb(phb);
209 	pcibios_fixup_new_pci_devices(phb->bus);
210 	pci_bus_add_devices(phb->bus);
211 	eeh_add_device_tree_late(phb->bus);
212 
213 	return phb;
214 }
215 EXPORT_SYMBOL_GPL(init_phb_dynamic);
216